Monomeric polar-substituted thioamides and their preparation



Patented May 21, 1940 h MONOMERIO POLAR-SUBSTITUTED TRIO- AMIDES AND THEIRPREPARATION William Edward Hanford, Wilmington, DeL, as-

signor to E. I. du Pont de Nemours & Company, Wilmington, Del., a corporation of Delaware No Drawing. Application September 15. 1938,

Serial No. 230,142

18 Claims.

This invention relates to new surface-active organic compounds and their preparation, and

more particularly to certain types of thioamides.

The present application is a continuation-in-part 5 of my 'copendin'g application Serial Number 137,149, filed April 15, 1937.

This invention includes among its objects new secondary monomeric polar-substituted thioamidea and their preparation. A further object is new surface-active agents and their preparation.

Another object is to prepare surface-active secondary thioamides in which the thlocarbonyl "residue is attached to carbon as well as to amido nitrogen. Still another object is to prepare thioi5 amides of said type which also contain a long 4 open hydrocarbon chain. A more particular object is to prepare long-chain sulfated and sulfonated secondary amides of carbpthionic acids in which the thiocarbonyl group is attached to carbon as well as to amido nitrogen. Other objects will be evident from the description which follows.

The term polar group is used herein to describea polyatomic group containing an inor- :5 ganic element bound to a different and polyvalent element by a definitely though not perhaps completely polar bond (see Lewis, Valence and the Structure of Atoms sand Molecules, Pa e 84). Byfar the most important water solubilizing polar groups are the hydroxyl, tertiary amino,

acid (containing ionizable hydrogen, e. g., sulfo, sulfate, carboxyl, etc.) and salt groups. The term secondary thioamide" requires that the amide nitrogen or nitrogens have attached there- ;iS to one and only one amido hydrogen atom.

, The objects outlined above are accomplished by the following invention which comprises secondary, surface-active, monomeric thioamides of carbothionic acid, which amides contain a 4.0 w'ater-solubilizing polar group and have the thiocarbonyl s II c radical or radicals attached by one valence to "carbon and by the other valence to snido' nitrogen. In the preferred process embodiment of the invention, a nitrile and "hydrogen sulfide are reacted with an amine having at least one pri- 5o mary amino group which is attached toan aliphatic carbon atom, i. e., a carbon atom which isnot a part of anaromatic ring, the amine and ,nitrll'e belngtso selected that (a) one 'of them contains a polar-N W difleient from thereact- '5 groups, athe sum-otthe nitrile and primary amino groups is less than four, and (c) in the case of polyfunctional reactants having a plural ity of reacting groups, the reacting groups are separated by a chain ofat least two carbon atoms contiguous therewith and preferably at least athree carbon atoms in the case of polyreactant nitriles. That is, a monoamine may be reacted with hydrogen sulfide and a mononitrile .or a dinitrile and a diamine may be reacted with'hydrogen sulfide and a mononitrile, but the reac- 10 tion of a polyamine with hydrogen sulfide and a polynitrile is not within the scope of the present invention as in such case a monomeric thioamide would not be obtained. When a polyfunctional reactant, e. g., a dintrile or a diamine is em- ,15 ployed; the reacting groups should be separated by a chain of at least two carbon atoms contiguous therewith, i. e., carbon atoms which are in the chain of which the nitrile or amino groups are a part. In the case of a polyreactant nitrile, 2c the nitrile groups are preferably separated by chains of at least three carbon atoms to prevent formation of iminothioimides.

The following equation, in which R and R are organic radicals, one of which contains a polar 5 group, illustrates the reaction involving a mononitrile and a monoamine. The more complicated combinations can be represented similarly.

R-cN+nsn+H,N-R' Rli'|JNHR'-l-NH3 Alternatively, these surface-active secondary carbothionamides can be obtained by reacting hydrogen sulfide with a nitrile and a primary aliphatic amine (in which the sum of the amine and Sit nitrile groups is less than four and. in which, when polyfunctional, the nitrlle and amine groups are separated by chains of at least two carbons), and then reacting the resulting thloamide with a reagent, such as a sulfating agent; which will to introduce a polar group. It is to be noted that the present invention does not deal with, nor is either process of theinvention applicable to the preparation of; amides. surface active or othem wise, of thiocarbonic'acid (1. e1, iniour), it which the thiocarbonyl group is attached only to nitrogenmolecule derived from the nitrile. The following comprehensive formulas represent the two subclasses of each group. The various Rs represent hydrocarbon radicals; Z represents a polar group; and v, w, x, and y are whole numbers representing proper valences In these formulas the various R's (R R may be aliphatic, aromatic,. araliphatic, or cycloaliphatic, but preferably hydrocarbon. Thus R R, R and R. may be alkyl, aryl, aralkyl, or cycloalkyl; and R R R and R may be alkylene, arylene, aralkylene or cycloalkylen'e. They may be saturated or unsaturated; straight or branched chain; monocyclic or polycyclic. The number of types and combinations is so numerous as to preclude illustration of each, but the following table will indicate the names, formulas, derivation, and class and sub-class of typical thioamides within the limits of the invention. So far as is Known, any others of the indicated types may be similarly represented and prepared.

Thioamides Class Name Formula Prepared from H18 (A l) N-thiolauryltaurlne C H (;JNHCH,CH S 0 H Lauronitrile and taurine.

(A l) N-thiolaurylglycine C H fiNHCH,O00H Laurouitrile and glycine.

/CH: I Al Thiosteary]aminoethyltriniethylam- C1711 CNH-CH:CHr-NCH3 Stearonitrile and dimethylamino- (0 1) monlummethosulfate. ethylamine, and then reaction S CHgO-SOrO OH; with dimethyl Suliate. 11) N-thiostearylglycine G; H |3-NHCH;CO0H Stearonitrile and'gljycine. v=

S Al l-thiol'aurylamino-fi-sullatopropane-- 011E223ONH-CHCH;CHOSO:OH Lauronitnle and 3-aminopro- II panel, and snliation of the product.

H N-thiomyristyltauxine C1rHar(|'lJ-NHOHrCHaS0|H Myristonitrile and taurine.

I CH: Al l-thiocapryloylamino-fi-dim ethyl- C1H15C-"NH'-(OH2)QN/ Oaprylonitrile' and N ,N -dimeth- 1) I amlnohexane. II ylhexamethylenediamme.

V S OH:

A2 Sulfonated N-octylthlohenzamide.... H0 8 B'enzonitrile and n-octylamine, h and sulfonation of the product.

A2 fi-carboxy-Ndodecylthiovaleramide. HOOC(CHz)4C-NH-CnHza ip i .mononitrile an (w=1) H n-dodecylamme.

K S A2 N-octadecyl-a-piperidylthioacetamidea-piperidylacetonitrile and n- (w=1) N-(JH,-C-NE- Q, E octadecylamine. g A -Z N-octyl-e-dimeth laminothloca re- CH N CH C-NH-C' -di yl p and (10:1) nude. Y D a): 9)r- I 5 111 nfldwmmme.

A2 fi-sulfato-N-he tadec lth' HOSO O-GH C H A lonitrile and n-heptadeoyl- (w=1) amide. p y mpmpmn r'ofirfi NH film, and sulfation of the product.

. S l N,N-bis(w-trlmethylammoniumhexll Succinonitrlle and lI,N -d1meth- (i=2) yl)thiosuocinam:lde chloride. (GH:) CNH(CHg)q-N(CH ylhexamethylenedianune, and

. reaction of product with matho1 yl chloride.

. S I Al N,N-bi8(w-dimethylaminohexyhthlo- {I Adlponitrile and IfT.N -d1methyla lpn id -(CH2) zC-NH-(CH;);N(CH1): 2 hemmethylenediamine.

A- -1 N, N-bis(w-carboxyamyl)thiosnccin- S I Sucdnonitrlle and e-aminocapro- (v=2) amide. ic acid.

CH2C-NH(CH:)5C0OH 2 13-2 bis-a-d.lmethylaminothioacetylhexa- .s I Dimethylemino-acetonitrile and (F methylenediamine. g hexamethylenedlamlne.

(CHahN-CHr- -NH(CH:):- 2 13-2 bis-B-sulfothio to ion ldecameth l- S I fi-snlfonropiononitrile 811d 11:2) enediamlne. p p y y (U: methylenediamine.

- HO:S(CHa):- NH(CH:)5 2 B2 Enlisted bis-thiovinylaeetylhexameth- I S Vinylacetom'trile and hexametli' (1I=2) ylenediamine. I: ll 1 .HQSO; ylenediamine, and sulfation of CHFOH-CH:CNH(CHa): 2 the produet. 28-2 Sulfated bls-thiomethacryldecameth- CH C-CNH CH -met acry trile and e (u==2) ylenedlamine. I .H1S04 methylenediamlne, and sulfa- 7 H30 2 tion of the product. 13-1 N N-bls(N-thlolauryl-fl-aminoethyl)- c m c.Nn-cn on N on Lauronitrfle and N,N-bis (pdhnethylammoniummethosulfate. u r a oethy ethy a and 2 -C O -OCHa reaction of product with dimethylsultate.

- with hydrogen sulfide.

' The thioamidcs of the present invention which find greatest utility in the surface-active field are those which are prepared from ingredients so selected that the final compound contains at least eight carbon atoms in a straight, open hydrocarbon chain. The majority of those given in the above table are of this kind.

In carrying out the process, the amine and nitrile are dissolved in an inert solvent which preferably boils 70-180? C. This solution may then be saturated with hydrogen sulfide at a temperature of -10 C. and subsequently heated in an autoclave at 100 C. or above for several hours. Alternatively, hydrogen sulfide may be passed into the solution 0! nitrile and amine at atmospheric pressure whileheating to the refluxing temperature of the solvent until substantially no more hydrogen sulfide is absorbed. The thioamide is then isolated by removing the solvent and crystaliizlng or distilling tho'residue.

The more detailed practice of the invention is illustrated by the following examples, wherein parts given are by weight. There are of course many forms of the invention other than these specific embodiments. a

EXAMPLE I N- (p-hydromyethyl) thz'olauramide In a pressure vessel are placed 15.0;parts of p-aminoethanol, 37.0 parts of lauronitrile, and 50 parts of ethyl alcohol. This mixture is saturated with hydrogen sulfide at a temperature of C. and the reaction vessel sealed and heated for 8 hours at 100 C. It is then opehed and the alcohol evaporated 011. The solid. product which remains is N- (fl-hydroxyethyl) thiolauram'ide of the 'formula HB H)IO' NH'-'CHTCH OH It is soluble in benzene, has surface-active properties, and is'useful as a wetting agent. Evidence of its chemical character resides in the method of. synthesis and in the fact that, on heating in benzene solution, hydrogen sulfide is evolved and 2-undecyl-4, fi-dihydrooxazole is formed.

EXAMPLE II p Sodium N- (s-sulfo-ethyl) thiooieamide To parts of water and 100 parts of alcohol in a pressure vessel are added 14.7 parts of finely round sodium fi-aminoethanesuiionate and 28.3 parts of oleonitrile, and the mixture saturated The pressure vessel is i sealed and heated .for at least 18 hours at 100 C.,

after which it is cooled, opened, and the contents evaporated to dryness. A wax-like paste is obtained which is soluble. in water and produces a heavy foam on shaking. This material, which is the crude sodium salt orN-(p-sulfoethyhthieoleamide, of the formula omwnmcn-crr-wnor- -sn-onr-onr-so m can be purified by washing with acetone, dissolving the residue in 12-15% aqueous alcohoh and evaporating off the alcohol and water. A white solid is obtained which on analysis has a sulfur content which checks within experimental error that calculated forN- p-sulfo-ethyl') thiooleemide. s EXAMPLE 'III Sodium N-(fi-sulfoethyllthiolcwamide.

To 70 parts of alcohol and '7 parts of water in I a. pressure vessel areadded 15.0 of

It can be purified by washing with acetone and crystallizing the residue from alcohol and water. It is soluble in water to give a surface-active solution.

EXAMPLE IV Sodium N-(p-s1.zlfatoethyl) thz'olauramide One mol of N-(p-hydroxyethyl)thiolauramide, obtainable as in Example I, is dissolved in ether and cooled to about 20 C. To this solution is slowly added 1.1 mols of chlorosulfonic acidQthe temperature being kept at 20-25 C. The reactionmixture is allowed to stand at room temperature for several hours, the ether removed by distillation and the residue (free sulfuric acid) dissolved in dilute aqueous sodium hydroxide. There is thus obtained an aqueous solution ofsodium N-(p-sulfatoethyl)thiolauramide oi the formula I II om-wmm-o-nn-cm-orn-o-soln This compound has surface-active'properties and is useful as a detergent.

EXAMPLE V Sulfonatcd N-dodecylthiobenzamids-sodium salt In areaction vessel equipped with a reflux condenser, a stirrer, and a gas inlet tube are placed 103 parts of benzonitrile, 203-5 parts of n-dodec-1 ylamine and 500 parts of ethylalcohol. The reaction mixture is heated to boiling, and hydrogen sulfide is passed into the solution for 16- hours. The alcoholis then distilled off, leaving a. brown oil which boils at about 235 C. at 3 mm. pres-- sure. This oil is dissolved in low boiling gasoline and the solution cooled. Yellw plates oi N-dodecylthiobenzamide are obtained, melting point 44-45 C. This compound is sulfonated by dissolving the entire quantity obtained in 2 mole of 100% sulfuric acid at -45 0., allowing the mixture to stand for about 6 hours, and then pouring it into ice water. This solution is then neutralized with sodium hydroxide, andextracted' with low-boiling gasoline to remove. any unsulfonated material. There is thus obtained an aqueous solution of the sodium salt of. a ring sulionated N-dodecylthiobenzamlde. oi" the formula some It is soluble inwater and has surface-active properties.

EXAMPLE VI ill-'- (p-dimethyZaminoethz/l) thiooleamidc in a pressure vessel are placm 10 parts oi' N, lt-

dimethylethylenediamine (c-di'methylaminoethylaminenwfi or oleonitrile, and 1 of ethyl alcohol. Thlsreaction mixtuceis saw-- rated with hydrogen sulfide, and the vessel mlsii and heated or 10 hours at C. It is then opened and the alcohol evaporated on. The resuiting product is N- (pl-dimethylaminoethyl) thiooleamide of the formula It is soluble in dilute hydrochloric and acetic acids and is surface-active. On treatment with methyl iodide or dimethyl sulfate, the product is converted into surface-active quaternary ammonium salts which are stable to acids and bases.

EXAMPLE VII I N-(E-carboryan yl)thiolaummide-Sodium salt In a pressure vessel are placed 17 parts of sodium e-aminocaproate, 15 parts of water, 100 parts of ethyl alcohol, and 18 parts of lauronitrile. This reaction mixture is saturated with hydrogen sulfide at C. The vessel is then sealed and heated in a furnace at 100C. for 8 hours, after which it is cooled and opened, and the contents evaporated to dryness. The resulting solid is the sodium salt of N- (e-carboxyamyl)thiolauramide; of the formula It is soluble in water and shows surface-active properties.

In place of the pure lauronitrile used in Examples I, III, IV, and VII, it is possible to employ the mixture of nitriles obtained from coconut oil acids and ammonia in the presence of a dehydration catalyst, as described in Wortz, Serial No. 173,196, filed November 6, 1937. In such case, mixtures of thioamides will be obtained. The respective N-substituted thioamides will be present in about the following proportions: Thiocaproamides 2%, thiocaprylamide's 9%, thiocapramides 10%, thiolauramides 45%, myristamides 20%, thiopalmitamides 5%, thiostearamides 9%, and thiooleamides and thioarachidamides in traces.

As previously indicated, the principal process described herein can be carried out with any nitrile and any amine containing a primary amino groupattached to an aliphatic carbon, one of these reactants having a polar group, subject to the considerations that the sum of the primary amine and nitrile groups shall be less-than four, and that the amine and nitrile groups of diamines and dinitriles shall be separated by chains of at least two carbons. The polar group should of course be one which does not interfere, at least not to any great extent, with the thioamide-formin'g reaction, and may be a hysulfonate, p-cyanodimethylaniline, N-dieth'ylaminocapronitrile, furonitrile, nicotinonitrile, mhydroxybenzonitrile, mixed naphthenic acid nitriles; acrylonitrile, methacrylonit'rile, allyl cy anidaii2 hydroxystearonitrile, fumaronitrile, N-

phenylaminoacetonitrile, N-diethylaminoaceto- 'nitrile, .phthalonitrile, and l -cyano-l-pentene.

' 31 Speciflcfamines suitablefor use in the process thioinclude: p-aminoethanol, B-aminoethanesulfonic acid, sodium B-aminoethanesulfonate, N,N- dimethylethylenediamine, N,N dimethylhexamethylenediamine, glycine, e-aminocaproic acid, ethylamine, butylamine, ethylenediamine, n-dodecylamine, 9,10-octadeceny1amine, hexamethyllenediamine, decamethylenediamine, octadecamethylenediamine, 1,4-cyclohexylenediamine, noctadecylamine, n-heptadecylamine, biS-oz,a'-di aminodipropylether, benzylamine, 2-ethylhexy1- amine, 8-aminopentadecane, p-hydroxybenzylamine, m-diethylaminobenzylamine, allylamine,

methallylamine, and 1-amino-5-hexene.

As also previously indicated, the present invention is general to surface-active, i. e., polarsubstituted, monomeric amides of carbothionic acids in which the thiocarbonyl structure is attached to carbon aswell as to amido nitrogen, and in which the amide groups are preferably all secondary, by which is meant containing the structure. All the products of the examples, all of those in the table, and those obtained from appropriately selected pairs of amines and nitriles in the above lists are of this type. The most useful types are those having an open hydrocarbon chain of at least eight carbon atoms in some portion of the molecule, and these therefore form a preferred class.

In carrying out the present process, temperatures of from about 50 C. to about 200 C., and in some cases higher, may be used. The temperature should be below that at which destructive carbonization takes place. The pressure may be atmospheric or above, depending on the particular method of reaction chosen. The diluent may be any organic liquid which is inert to reactants and product, a solvent for the reactants, and a solvent or non-solvent for the product. Suitable specific diluents include ethanol, butanol, pentanol, dioxan, acetone, c-methoxyethanol, toluene, xylene, benzene, and the like. The ratios of reactants given in the examples are not limiting. A slight excess of amine over that required to react with the nitrile is preferable, but the process can also be operated with excess nitrile. A slight excess of hydrogensulfide is preferably, though not necessarily, used in all cases.

The new compositions covered in this case belong to the class of surface-active or capillary used by themselves or in combination with other surface-active agents in any reaction in which surface-active agents having colloidal properties have heretofore been used. In general, they may be employed for any of the purposes given in Downing and Johnson application Serial Number 200,530, filed April 6, 1938.

The above description and examples are intended to be illustrative only. Any modification of or variation therefrom which conforms to the spirit of the invention is intended to be included within the scope of the claims.

I claim:

LA monomeri surface-active, amide of a I carbothionic acid in which all thiocarbonyl groups are attached to carbon, said amide containing a water solubilizing polar substituent.

2. A surface-active amide of a monobasic carbothionic acid in which the thiocarbonyl group is attached to carbon and all the amide groups are secondary, said amide containing a water solubllizing polar substituent.

3. A- monomeric, polar-substituted, surfaceactive, amide of a carbothionic acid in which all thiocarbonyl groups are attached to carbon and all the amide groups are secondary, said amide containing an open hydrocarbon chain of at least eight carbon atoms.

4. A monomeric, polar-substituted, surfaceactive, amide of a monobasic carbothionic acid in which the thiocarbonyl group is attached to carbon and all the amide groups are secondary, said amide containing an open hydrocarbon chain of at least eight carbon atoms.

5. A monomeric amide of a carbothionic acid in which all thiocarbonyl groups are attached to carbon and all the amide groups are secondary, said amide also containing a polar group selected from the class consisting of hydroxyl, tertiary amino, acid and salt groups.

6 A monomeric amide of a carbothionic acid in which all thiocarbonyl groups are attached to carbon and all the amide groups are secondary, said amide also containing an open hydrocarbon chain of at least eight carbon atoms and a polar group selected from the class consisting of hy- 7, in which R has an open hydrocarbon chain of at least eight carbon atoms.

10. A monomeric amide of a carbothionic acid in which all thiocarbonyl groups are attached to carbon, all the amido groups are secondary and there is present an acid group.

11. A monomeric amide of a carbothionic acid in which all thiocarbonyl groups are attached to carbon, all the a'mido groups are secondary and there is present an acid group and a hydrocarbon 'chain of at least eight carbon atoms.

there is present a sulfur acid group.

13. A monomeric amide of a carbothionic acid in which all thiocarbonyl groups are attached to carbon, all the amido groups are secondary and there is present a sulfur acid group and a hydrocarbon chain of at least eight carbon atoms.

' 1.4. Process for preparing surface-active thioamides which comprises reacting hydrogen sul fide with a nitrile and with an amine having at least one primary amino group which is attached to an aliphatic carbon atom, the amine and nitrile being so selected that one of them contains a polar group difierent from the reacting groups, the sum of the nitrile and primary amino groups is less than four, and, when either has a plurality of reacting groups, said groups are separated by a chain of at least two carbon atoms contiguous. therewith.

15. A monomeric, surface-active amide of a carbothionic acid in which all thiocarbonyl groups are attached to carbon and all the amide groups are secondary, said amide containing a water solubilizing polar substituent.

16. Sodium N-(beta-sulfoethyl)thiooleamide.

17. Sodium N (beta-sulfatoethyl) thiolauramide.

18. N- (beta-dimethylaminoethyl) thiooleamide.

WILLIAM ED ARD HANFORD,

Certificate of Correction Patent No. 2,201,171. May 21, 1940. WILLIAM EDWARD HANFORD It is hereby certified that errors appear in the printed specification of the above ered patent requiring correction as follows: Page 1, second columiiil, line 15, for

n dintrile read din'itrile; page 3, first column, line 10, after the word b0 insert at; line 45, for -4, 5- read -4,5-; and second column, line 48, for Yellw read Yellow; age 5, first column, line 84, claim 7, in the formula, for v read 0; and that the said 7 tters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Oflice.

' Signed and sealed this 17th day of September, A. D. 1940.

IHENRY VAN ARSD'ALE,

, Acting Commissioner of Patents. 

